Method for Formation of Alumina Coating Film, Alumina Fiber, and Gas Treatment System Comprising the Alumina Fiber

摘要

In the formation of an oxide film on an aluminum fiber, it has been difficult to form a thick alumina coating film on the aluminum fiber which already has a natural oxide film formed thereon. To overcome this problem, there is provided a method for forming an alumina coating film which enables the deep penetration of oxygen into an aluminum fiber by employing a three-stage heating treatment and an alumina fiber formed by the method. Also provided is a system for producing water by photocatalytic reaction, in which a photocatalyst comprising the alumina fiber coated with titania is irradiated with light from a light source to generate an active oxygen species, diffusing the active oxygen species in water to impart the function of the active oxygen species to water. The system can perform washing by utilizing an oxidation reaction with the resulting water. Further, provided is a gas treatment system which comprises the alumina fiber coated with titania to impart a photocatalytic function to the aluminum fiber.